HTE007KDS

I have a 2007 Edge AWD SEL. I have the same issue with my navigation system. I have version 4P nav dvd. One day drive down the road and my nav displayed a message saying "There was an error the dvd maybe dirty. Try cleaning it.". I took the dvd out. It was clean. I wiped it anyway and inserted the disk back in the nav unit. But I got the same error. I called Ford navigation tech support 1-800-565-3673. The tech said I should try a inserting a more recent version of the nab dvd. The dvd cost 199.00. The kicker is you cannot return it if you open it. killawhalen, what version of the dvd did you purchase?